Question about Naval Stacks

I keep it simple, lock ships into battle with a stack of submarines and then approach with a stack of destroyers and blowing them to peaces without taking damage. You will lose subs but they are so cheap. A pack of destroyers and subs working together are highly effective, take low upkeep and as they don't use a lot of manpower it will result in great stats too.

My favourite weapon of the sea is cruiser or battleship. It has a long range, which means i can actually destroy land troops without having anyone will up there or without getting myself damaged unless a SP artillery is on shore.